Products of photosynthesis: oxygen, CO2 uptake and measuring rate
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Flip to reveal answersWhat are the two PRODUCTS of photosynthesis?
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All 12 Flashcards — Products of photosynthesis: oxygen, CO2 uptake and measuring rate
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Question
What are the two PRODUCTS of photosynthesis?
Answer
**Glucose** (chemical energy) and **oxygen** (a released waste gas).
Question
Which gas does photosynthesis RELEASE?
Answer
**Oxygen (O₂)** — a waste product, given off from the splitting of water.
Question
Which gas does photosynthesis ABSORB?
Answer
**Carbon dioxide (CO₂)** — a raw material whose carbon is built into glucose.
Question
Where does the oxygen given off in photosynthesis come from?
Answer
From the **splitting of water** during the reaction.
Question
Why does an illuminated aquatic plant give off bubbles?
Answer
The bubbles are **oxygen**, a product of photosynthesis released in the light.
Question
Name three ways to measure the rate of photosynthesis.
Answer
**Oxygen produced** (bubble count / gas volume), **carbon dioxide taken up** (CO₂ indicator), and **pH** of the water.
Question
What does a CO₂ (hydrogencarbonate) indicator show?
Answer
It changes **colour** with the dissolved carbon dioxide level — as the plant removes CO₂, the colour shifts.
Question
Why does faster photosynthesis make the water's pH RISE?
Answer
It **removes carbon dioxide**; dissolved CO₂ is acidic, so less CO₂ means **less acid** and a **higher pH**.
Question
How does counting bubbles measure the rate?
Answer
**More bubbles per minute** means **more oxygen** is being released, so photosynthesis is **faster**.
Question
Define the rate of photosynthesis.
Answer
How **fast** photosynthesis is happening — e.g. how much **oxygen is produced** (or CO₂ used) each minute.
Question
Does removing CO₂ from water make it more or less acidic?
Answer
**Less** acidic — dissolved CO₂ is acidic, so taking it out raises the pH.
Question
How are the gas changes of photosynthesis different from respiration?
Answer
Photosynthesis **releases O₂ and absorbs CO₂**; respiration does the opposite (uses O₂, releases CO₂).
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Photosynthesis
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